Motor attachment for sewing machines



Patented Oct. 13, 1925.

frosrnn F. HIL L IX, .or c EvELAitn "onto, vassIeiiion", To, wnlrnisnwme COMBQANTYQ F L VEI AN r .1 );v s QOB'RQBATIQNI QF OHIQEmcronsarrncniwnnmroasnwme meenmnsg Applicationrfiled' April-.15,

To. all whom itmay. concern: I

Be it known that I, Fos'rnn F. H ll-LIX, a citizen; oft-he; United.States, residing-at Cleveland, in the county of Guyahcgafand State of;Ohio, have/invented acert'ain new and useful Improvement in MotonAttachements for. Sewing Machines, of which. the following is 2 a full, Iclear. andv exact description.

This invention relates to motoriattachr ments for sewing machines andhas t'or its object the; provision of. anew. mounting or manner ofsupporting the =motor; from the head by which an exceed in gly simplemotor support may be ut-ilizedwvhichat the-same time brings about a;very compact. arrange ment, and-an exceedingly eflicient drivingzrelationv betwee'nithe friction driving-pulley. of the motor and thehand heelof the sewing machine head. Y i f g v A further. object is;t'oprovide amounting which isespecially adapted for;sewingv ma? chines ofthe portable type, the mounting being of such a nature; that when themotor is supported on thehead it does not project outwardly beyondthe.;-b.a se -;so.- as to. require any change in or enlargement:OfE'l'llG. case whichis designed to be-fitted 0ver .-t-he head. Stillurther5the invention aims to provide a mounting wherein the frictiondriving pulley of the. motor may be maint-ained in good -.drivingrelationship with the hand wheel of the head; and .which candoe ad.-justedit conditions require, to vary the pressure between the pulley andhand wheel without altering the position.ofsthcmotor, or requiring't-heuse of springs: to. cause the desired frictional engagement between thepulley and hand wheclt Stillfurther the invention aims to provide adriving. pulley which has a yieldable. fi ic tional driving. portion ,which maintains-its shape'under high speed conditions andlpossesses toavery high: degree the feature of durability. v i e The invention may be.briefly summarized as consistingin certain novel details of;construction and. combinations and arrangements. of. parts whichwilllb'e described ill-.tli specification and point ed out inrthe appended claims.

In the accompanying sheet of'drawings wherein I have shown thatembodiment of my invention wherein-the attachment. is appliedto aso-called portal-file sewing machine,

1922. swarm. 5149, 830

Fig. 1' is a rearviewofiathe machine with the motor applied; in drlvingrelation to the andwhe lgpartsbeing in sectionyllig. Q S an end;viewlooking toward the right of Fig. 1.; Fig. 3zisa detail.-v-iewshowingi'n section. the.frictiondrivingpulley Eig; 4 is a face: view of?the a bracket by. which the motor is: attached to the; en'dof the head;gszasect onal view t rough hebmc let alongthel'ine 5 5:ot Fig.4,showingaportionof the head to. which the bracket is; atachedyand: Fig pa iew: o he bracket: attached to't'the" headta portion of the latterbeing shown in section.

l efi rr ngi to he raw-ings, 1c .repr sents .the upright: portion of:the; arm of the head-of-thesewing machineand 1 1' the' liorizontal;portiom. Likewise-'12 represents the hand. wheel: and 13 the wooden baseupon which the hea'dis mounted, the1sewingzmachine. shown" beingstandard. sewingfmw chineiof the portablegtype, which when not in useis; adapted to: be enclosed. in; a case, and when 1 in use; is supportedon, a; table or other convenientsupport,

For the purpose ofielectrically' drivingthe sewing machine, I provide.In improved motor attachment which .incln esia small electric motor 14.;In.this.instance the motor is mounted on the lpr-i ght. portion 10 ofthe arm of the. head, and itiisarranged beneath the hand wheelalongside. the .end of the head; slightly to: the: rear thereofi. oFurther, it will ;be :noted that the motora isssupported in inclinedposition-iwith 'its axis. in. an. in"- clined line which 1 intersectsrand is at, right angles to the axis of. the; shaft on which the handwheeli12 is mounted. To. bring; this about the lowerendlof motor is 6X-tended. slightly into a ,recess 1j3f of the .base in. order-.tliat amotor 1 of. the size having sufficient. power. to. drive .th emachine athigh speed .may be positioned as shown; A

furtheraadvantage, of .this feature lies in; the fact that av,rlieostat. may. be employed with this. motorv located; in. the basewithout; reqniring any external conductors to connect the motontothe'r-heostat. I

By reference to 1' and 21 it; willtbe observed. that. no. partoi'themotor projects beyondtlieontlineor. confines ofthevbjase .13, so that:itloecomes' iinnecessary to enlarge-the caseeinwhichthelhead of themachine. is designed to; be enclosed when thee machine is not in use. i

llO

This arrangement of the motor allows for an exceedingly simple butefficient supporting or attaching means between the motor and head. Thisis in the form of a bracket 15 which is preferably formed of sheetmetal, though it may be formed of cast metal, for with the pulleyreferred to presently, the bracket need not be of spring material. Thisbracket has a portion 15 which lies flat against, and is secured to thehead, and in this instance to a flat boss 10 cast on the end face of theupright portion of the head a short distance above the base 13. Thisbracket is preferably secured to the boss by a single screw 16 passingcentrally through the portion 15 of the bracket, and the bracket is thenheld from turning on the boss by a pair of tongues 15 which are bentinwardly into notches at the top and bottom of the boss 10*.Additionally the bracket is provided with a laterally offset anddownwardly extended portion 15 which is secured to the frame or body ofthe motor.

In this manner the motor is effectively supported by a bracket which canbe pro duced inexpensively, and which may or may not be of springmaterial, with the driving member of the motor in proper relation to thehand wheel.

The driving means between the motor and hand wheel is in the form of atapered friction pulley 17 which is secured on the upper end of themotor shaft 18 in the manner shown in the drawings, the pulley beingtapered and engaging the outer side face of the hand wheel rim. It willbe obvious therefore, that a proper driving relation between the motorand hand wheel can be obtained by adjusting the pulley lengthwise of themotor shaft and then by securing it in place by means of a set screw 19or equivalent means. The adjustability of the pulley is particularlyuseful when a rigid bracket is employed, or if the bracket is formed ofspring or elastic material when the spring or elasticity is not reliedon to hold the pulley in engagement with the hand wheel.

As a further feature of this mounting I have provided a pulley which hasnoiseless driving engagement with the hand wheel, and which is capableof years of use without requiring replacement, and very little, if anyadjustment lengthwise of the motor shaft. The pulley here shown iscomposed of a body portion 17 of rubber whose out-er periphery istapered as shown. In forming this pulley opposite sides thereof aresqueezed and held between a pair of disks 17 and 17, the former beinglarger than the latter, and both being preferably concaved inwardlysomewhat, substantially as shown in Fig. 3. In this instance the body ofrubber 17 and the clamping disks 17 and 17 are slipped onto a sleeve 17of a size which will fit onto the motor shaft 18, this sleeve having atone end a shoulder or enlargement 17 through which the set screw 19passes. In assembling the parts the disk 17 is first slipped onto thesleeve and is moved up against the shoulder 17 Then the body of rubberand larger disk 17 are slipped onto the sleeve and the disks are clampedtogether and the smaller end of the sleeve opposite the shoulder 17 e ispeened over or expanded as shown at 17 to hold the parts in their properrelationship.

The clamping pressure produced on the rubber by the disks 17 and 17bulges out the rubber between the disks and puts it under tension. Thenthe periphery is cut off, leaving a flat tapered surface which isdesigned to engage the handwheel 12. By so forming the pulley, inasmuchas the driving surface is under tension, and has a nat ural tendency tomove inward the inherent stresses in the rubber'resist the action ofcentrifugal force, and as a result the rubber will not bow outwardly andbe displaced by centrifugal force when the motor is operated at highspeed. Additionally a very durable wear resisting driving surface isprovided.

While I have shown the preferred construction, modifications may be madein the arrangement of certain of the parts without departing from thespirit and scope of my invention. For example, the main features of themounting may be employed without employing a tapered pulley, and adriving pulley construct-ed on the principle of that described above maybe utilized advantageously with the motor supported on the arm in adifferent position with respect to the hand wheel.

Having described my invention, I claim:

1. In combination with a sewing machine having a head with a hand wheel,a motor, and a bracket securing the motor to the head, said motor havinga tapered pulley frictionally engaging the hand wheel and secured on themotor shaft so that it may be adjusted lengthwise thereof to vary thepressure of the pulley on the hand wheel.

2. In combination with a sewing machine comprising a head having a shaftand a hand wheel, a motor attachment comprising a motor supported fromthe head with its axis at substantially right angles to the axis of theshaft and hand wheel and having a tapered friction driving pulleyengaging the hand wheel and secured to the motor shaft so that it may beadjusted lengthwise thereof to vary the pressure between the pulley andhand wheel.

In testimony whereof, I hereunto aflix my signature.

FOSTER F. HILLIX.

